PROJECT ABSTRACT The overarching goal of this proposal is to facilitate the development of Kar-Hai Chu, PhD, into an established, independent researcher with expertise in leveraging rapidly emerging tools of technology and computer science to optimize cancer prevention and tobacco control. Dr. Chu has a multifaceted and productive background in computer science, education, public health, and tobacco control, including completion of an NCI T32. However, he is now at the ideal stage to use the resources of this award to coalesce his expertise specifically around how powerful emerging mobile technologies and tools of computer science can optimally influence smoking cessation. Although many commercial smartphone applications (?apps?) have been created and marketed as tobacco cessation tools, none are based on scientific evidence. The proposed K07 will fill this gap. Dr. Chu received an institutional K12 award to prepare for this work; preparation included collecting pilot data, assembling his team, and learning about patient-centered outcomes research (PCOR), which will inform the design of this proposal. A PCOR-based approach is ideally suited for this research, because it will leverage relationships with multiple stakeholders in order to maximize the impact of the results. The research aims include: (1) assessing the usability of a leading online tobacco cessation app (Kwit) using a Patient-Centered Outcomes Research (PCOR) approach; (2) conducting a formal feasibility trial assessing integration of the Kwit app into the context of standard cessation treatment. Primary outcomes of the trial will focus on feasibility (recruitment, retention, stakeholder feedback). Secondary efficacy data from the trial will help inform a larger clinical trial to be proposed in an R01 grant application. In order to complete these aims, Dr. Chu will require additional training in several areas. The career objectives of this award are to: (1) develop expertise in the science of cancer prevention and tobacco cessation; (2) advance knowledge of new technologies and the implementation of mobile health applications; and (3) develop expertise in clinical research skills. These career objectives will be achieved through a combination of mentorship, conferences, workshops, and formal coursework. Brian Primack, MD, PhD, will serve as the primary mentor; Dr. Primack leveraged his own K07 into multiple R01 and R21 awards. Complementary mentorship will be provided by Esa Davis, MD, MPH, Director of the Tobacco Treatment Service, Jian Min Yuan, MD, PhD, Co-Leader of Cancer Epidemiology and Prevention at the Hillman Cancer Center, as well as an outstanding team of additional experts in PCOR, advanced statistics, mobile health technology, tobacco health behavior, and smartphone application. This study addresses a serious problem in tobacco cessation through an innovative PCOR-based approach, while combining resources from an academic/industry collaborative effort. This career development award will help Dr. Chu transition to an independent career in cancer research and mobile health technologies.